Entities common properties.
Enabled: indicates whether or not the geometry will be used when simulation is run. It allows you to deactivate an entity without removing it from your model.
Relative position: sets the entity's position, using the parent entity as a reference point. Actually, only rendered entities are positioned relative to physical geometries (for this, the two must be associated). Physical geometries are either positioned relative to a reference PHX, or to the world's reference point (sometimes referred to as "identity matrix" in Marilou).
X, Y, Z: sets the entity's position along these axes (see Axis system and coordinates).
Properties in the Exec group have an effect when simulation is running (specific execution window).
Compute Shadows: indicates whether or not the geometry should generate a shadow. Use the Display panel to enable shadow display during modeling. Physical geometries ("physics only" display mode) display shadows, even if they are invisible (in render display only).
Marilou 2009: Physical geometry with the "physics only" display mode, displays its shadow even if entity is invisible unless attached 3D entity owns its own shadow. Also, shadowing is active only if geometry is lightened by a light with "Generate dynamic shadows" property checked.
User can select & move: indicates that you may move an entity while simulation is running. If you have having trouble selecting an entity during simulation: deactivate this option in order to limit the number of entities that may be selected.